Once upon a time I had the idea that in time immemorial it was actually normal for elves to be born either drow or elf. For various reasons, elf and drow philosophies were always at odds, and they fought endlessly. In a time so ancient that it has been lost to memory, the elves triumphed in bloody genocide over the drow, then buried the memory so deep in their shame that it was all but forgotten that there was ever another type of elf.
Millennia later, when some elves were trapped in the caverns below Golarion during Earthfall, they learned the startling truth when the light aspected elves spontaneously inverted into dark aspected drow. It turns out their species lives in an ongoing balance between dark and light. One upshot of this is that because there are so few drow comparatively, their innate magical powers are were vastly enhanced over those of elves (referencing 1e drow noble abilities).
I don't remember what the philosophical differences i came up with were, but even back then I was keen on changing up the "born evil/good" vibe and was probably working in terms of like "light fae whimsy vs dark fae caprice"
My quick fix would be to make Caligni a versatile heritage so elves can be Caligni too. Caligni and Drow have a very similar vibe of underground weirdos warped by dark forces, plus the Caligni are commonly called Dark Folk, which could reasonably refer to Dark Elves as well.
There is nothing stopping a player from making a cavern elf from the Darklands with dark skin and red eyes.
I am just glad I can make one and not have all the baggage of being from an evil race.